Traditional laminate and parquet floors are usually laid floating, i.e. without gluing, on an existing subfloor. Floating floors of this type are usually joined by means of glued tongue and groove joints. The same method is used on both long side and short side, and the boards are usually laid in parallel rows long side against long side and short side against short side.
In addition to such traditional floors, which are joined by means of glued tongue and groove joints, floorboards have recently been developed which do not require the use of glue and instead are joined mechanically by means of so-called mechanical locking systems. These systems comprise locking means which lock the boards horizontally and vertically. The mechanical locking systems can be formed in one piece by machining of the core of the board. Alternatively, parts of the locking system can be formed of a separate material which is integrated with the floorboard, i.e. joined to the floorboard even in connection with the manufacture thereof at the factory. The separate material may consist of an already machined part which is included in the joint system, but it may also be a part which after fastening is formed to a suitable shape. Fastening can take place with glue or mechanically. The floorboards are joined, i.e. interconnected or locked together, by different combinations of angling, snapping-in and insertion along the joint edge in the locked position.
The main advantages of floating floors with mechanical locking systems are that they can easily and quickly be laid by preferably various combinations of inward angling and snapping-in. They can also easily be taken up again and used once more at a different location.
Prior-Art Technique and Problems Thereof
All currently existing mechanical locking systems and also floors intended to be joined by gluing have vertical locking means which lock the floorboards across the surface plane of the boards. These vertical locking means consist of a tongue which enters a groove in an adjoining floorboard. The boards thus cannot be joined groove against groove or tongue against tongue. Also the horizontal locking system as a rule consists of a locking element on one side which cooperates with a locking groove on the other side. Thus the boards cannot be joined locking element against locking element or locking groove against locking groove. This means that the laying is in practice restricted to parallel rows. Using this technique, it is thus not possible to lay traditional parquet patterns where the boards are joined mechanically long side against short side in a “herringbone pattern” or in different forms of diamond patterns. It is known that floorboards can be made in sizes that correspond to traditional parquet blocks and in A and B design with mirror-inverted joint systems, and that such floorboards can be joined mechanically in a herringbone pattern (WO 03/025307 owner Välinge Aluminium AB) by various combinations of angling and snapping-in. Such floorboards can also, if the locking systems are designed in a suitable manner, be joined in parallel rows. Floorboards can also be designed so that laying in, for instance, a herringbone pattern, with long sides joined to short sides, can be made quickly and easily by merely an angular motion along the long sides. In such laying, a short side can be joined to a long side by the short side, for instance, being folded down upon a long side strip which supports a locking element. This locking element locks the floorboards horizontally. The vertical locking on such a short side is achieved by the boards being joined in a herringbone pattern at 90 degrees to each other. A new board which is laid by angling locks the short side of the preceding board and prevents upward angling. This extremely simple laying method can, however, when laying a herringbone pattern can only be provided in one direction. This is a great drawback at the beginning of laying when the space toward the wall cannot be filled with cut-off floorboards which are installed backwards, i.e. in the direction opposite to the laying direction. Such backward laying must then be made by snapping-in the short sides or by removing locking elements so that the boards can be moved together and glued. Otherwise, laying must begin with cut-off floorboards which are difficult to measure and time-consuming to install. Laying of a continuous floor surface covering several rooms requires extensive preparations and measurement since laying can only take place in one direction. Take up occurs in reverse order and practically the entire floor must be taken up if some boards that have been laid at the beginning of the laying are damaged. Such damage easily arises in connection with laying and is not noticed until the entire floor has been laid and cleaned. It would therefore be a great advantage if a herringbone pattern could be laid by merely an angular motion and in different directions.